CN104190840A - Die structure for hot upset forging of stainless steel bolt - Google Patents
Die structure for hot upset forging of stainless steel bolt Download PDFInfo
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- CN104190840A CN104190840A CN201410460977.1A CN201410460977A CN104190840A CN 104190840 A CN104190840 A CN 104190840A CN 201410460977 A CN201410460977 A CN 201410460977A CN 104190840 A CN104190840 A CN 104190840A
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Abstract
The invention belongs to the technical field of dies, and particularly relates to a die structure for hot upset forging of a stainless steel bolt. The die structure comprises a female die and a male die, wherein the male die comprises a first die shell, a first die core and a first cavity, the first die core is placed in the first die shell, the first cavity is formed in the first die core, the female die comprises a second die shell, a second die core and a second cavity, the second die core is placed in the second die shell, the second cavity is formed in the second die core, and a containing space for the bolt is jointly formed by the first cavity and the second cavity. According to the die structure, compared with the prior art, the female die and the male die are arranged to be of a split structure with parts replaceable, and thus replacement can be performed more conveniently and fast; if some part in a die is damaged, the die does not need to be scrapped as a whole, only the damaged part needs to be replaced, and therefore die cost is greatly reduced, and the service life of the whole die is prolonged.
Description
Technical field
The invention belongs to technical field of mold, particularly a kind of hot upset forging mould structure of stainless steel bolt.
Background technology
Particularity because of stainless steel, when comparing larger part with the upsetting of cold-heading method shaping head (bolt as T-shaped in stainless steel), head is because being out of shape the very easily flow harden of violent material, cause next step cold deformation of blank to become difficult, even if blank is again annealed and is carried out also easy burst-mode tool of cold forming again, because annealing must change the crystal structure of material, if annealing time is oversize, too thorough, can cause the refinement of whole blank crystal, blank deliquescing, having a strong impact on these needs has the mechanical property of the bar portion of suitable hardness and intensity (screw thread need to be shaped), thereby cause the serviceability of product to decline, if and employing guarantees the annealing time of the intensity of blank bar portion, blank head flow harden just can not be eliminated completely, easily causes frequent burst-mode during cold forming.
So generally adopting cold upsetting to be shaped than stainless steel bolt (bolt as T-shaped in stainless steel), the large upsetting of producing and selling on industry and market at present adds turning process or cold upsetting shaping heating hammer down forming process, because turning process is to remove at product surface the object that part material reaches shaping, in process, the fibr tissue of metal will inevitably be destroyed, have a strong impact on outward appearance and the mechanical property of product, production efficiency is low simultaneously, processing cost is very high, is unfit to do batch production.
And hot upset forging mold materials employing at present is the mould structure of full hot-work steel or hot upset forging wolfram steel outsourcing hot-work steel, shortcoming scarce, that ftracture or pull that ubiquity mould easily collapses, life-span is very undesirable, cause production cost higher, once and certain part is wherein damaged, whole mould all needs to change; Therefore,, in order to improve the performance of product and to reduce production costs, need the hot upset forging mould structure of a kind of stainless steel bolt of research and development badly.
Summary of the invention
The object of the invention is to: for the deficiencies in the prior art, and provide a kind of hot upset forging mould structure of stainless steel bolt, it can improve the service life of mould, the outward appearance and the mechanical property that improve product, make product quality more stable, and can save material and artificial cost, and owing to adopting split-type structural, therefore when wherein certain parts is damaged, can only change this parts, and need not whole mould is discarded.
To achieve these goals, the present invention adopts following technical scheme:
A hot upset forging mould structure for stainless steel bolt, comprises die and punch, and described punch comprises the first formwork, the first core rod and the first die cavity, and described the first core rod is placed in described the first formwork, and described the first die cavity is arranged on described the first core rod; Described die comprises the second formwork, the second core rod and the second die cavity, and described the second core rod is placed in described the second formwork, and described the second die cavity is arranged on described the second core rod, and described the first die cavity and described the second die cavity form the accommodation space of bolt jointly.
With respect to prior art, the present invention is arranged to die and punch the Split type structure of replaceable accessory, it is more convenient to change, if certain part in mould is damaged, do not need integral body to scrap, only need to change the position of damaging, thereby greatly saved die cost, improved the service life of mold integral.
As the hot upset forging of stainless steel bolt of the present invention, use a kind of improvement of mould structure, the outer surface of described the first core rod and described the second core rod is coated with open C jacket ring, and the material of open C jacket ring is spring steel.The spring steel material open C collar has good elasticity and toughness.This split, multiple prestress die nested structure have better toughness extended capability after making mould stressed, greatly increased mould at the anti-fatigue ability being subject to continuously under large impact force environment.
As the hot upset forging of stainless steel bolt of the present invention, use a kind of improvement of mould structure, all process through TD on the surface of described the first die cavity and described the second die cavity.The first die cavity after TD processes and the case hardness of the second die cavity reach the height of HV3000, compare common hot die steel and have better the mechanical properties such as high temperature resistant, shock-resistant, intensity, toughness and fatigue resistance.
As the hot upset forging of stainless steel bolt of the present invention, use a kind of improvement of mould structure, the material of described the first formwork and described the second formwork is hot-work steel.
As the hot upset forging of stainless steel bolt of the present invention, use a kind of improvement of mould structure, the material of described the first core rod is hot die steel, and it is specially Switzerland DIEVAR 8418 high performance hot-work die steels.Because the temperature of hot pier section moulding reaches more than 1000 ℃, therefore quite high to the requirement of mold materials, this hot die steel can meet this requirement.
A kind of improvement as the hot upset forging of stainless steel bolt of the present invention with mould structure, the outer surface of described open C jacket ring that is coated on the outer surface of described the second core rod is coated with Pre-stress cover.This structure can be alleviated the fatigue of mould because brought by large impact power greatly, exhaust effect is very good, more be conducive to the shaping of product head two salient points, be difficult for collapsing scarce, ftracture or pull, and conventional mould adopts whole common hot-work steel or whole wolfram steel structure and make its do not have exhaust effect or exhaust effect very poor, that the large impact power rear mold that is subject to mould easily collapses is scarce, ftracture or pull, therefore for existing mould, the present invention can improve the service life (more than one times) of mould greatly.
A kind of improvement as the hot upset forging of stainless steel bolt of the present invention with mould structure, described the second core rod comprises the secondary core rod that the main core rod that contacts with the head of bolt contacts with bar portion with bolt.
As the hot upset forging of stainless steel bolt of the present invention, use a kind of improvement of mould structure, the material of described main core rod is hot die steel, and it is specially Switzerland DIEVAR 8418 high performance hot-work die steels.Because the temperature of hot pier section moulding reaches more than 1000 ℃, therefore quite high to the requirement of mold materials, that Switzerland DIEVAR 8418 high performance hot-work die steels have is high temperature resistant, shock-resistant, high strength, high tenacity, superior plurality of advantages such as fatigue resistance, therefore can meet this requirement.The material of described secondary core rod is wolfram steel.The follow-up rolling screw thread processed that needs of bar portion due to bolt, can not there is distortion or pull, therefore it can not participate in distortion, therefore the secondary core rod contacting with the bar portion of bolt adopts wolfram steel material, the high-wearing feature of wolfram steel, having guaranteed that mould endoporus is more difficult is pulled by product, thereby can guarantee that mould is difficult for by garland, thus the service life of improving mould.
A kind of improvement as the hot upset forging of stainless steel bolt of the present invention with mould structure, the rectangle that the cross sectional shape of described the first die cavity is chamfering, the cross sectional shape of described the second die cavity be " recessed " font, the space that one of the combination composition of the two can receive bolts.
Accompanying drawing explanation
Fig. 1 is cutaway view of the present invention.
Fig. 2 is the cutaway view of convex mould of the present invention.
Fig. 3 is the cutaway view of die in the present invention.
The specific embodiment
Below in conjunction with embodiment, the present invention and beneficial effect thereof are described in further detail, but embodiments of the present invention are not limited to this.
As shown in Figures 1 to 3, the hot upset forging mould structure of a kind of stainless steel bolt provided by the invention, comprises die 2 and punch 1, and punch 1 comprises the first formwork 11, the first core rod 12 and the first die cavity 13, the first core rod 12 is placed in the first formwork 11, and the first die cavity 13 is arranged on the first core rod 12; Die 2 comprises that the second formwork 21, the second core rod 22 and the second die cavity 23, the second core rods 22 are placed in the second formwork 21, and the second die cavity 23 is arranged on the second core rod 22, the first die cavity 13 and the common accommodation space that forms bolt 3 of the second die cavity 23.The present invention is arranged to die 2 and punch 1 Split type structure of replaceable accessory, and it is more convenient to change, if certain part in mould is damaged, does not need integral body to scrap, and only needs to change the position of damaging, thereby has greatly saved die cost.
Wherein, the outer surface of the first core rod 12 and the second core rod 22 is coated with open C jacket ring 10, and the material of open C jacket ring 10 is spring steel.The spring steel material open C collar 10 has good elasticity and toughness.This split, multiple prestress die nested structure have better toughness extended capability after making mould stressed, greatly increase mould at the anti-fatigue ability being subject to continuously under large impact force environment.
All process through TD on the surface of the first die cavity 13 and the second die cavity 23.It is the super technique for hardening treatment of die surface that TD processes, its be under certain treatment temperature by workpiece as in molten salt of borax and Special Medium thereof, by the metallic atom in extraordinary fused salt and the carbon in workpiece, nitrogen-atoms, produce chemical reaction, be diffused in surface of the work and form several microns to more than 20 microns of one decks vanadium, niobium, chromium, titanium etc. metallic carbide layer.The first die cavity after TD processes and the case hardness of the second die cavity reach the height of HV3000, compare common hot die steel and have better the mechanical properties such as high temperature resistant, shock-resistant, intensity, toughness and fatigue resistance.
The material of the first formwork 11 and the second formwork 21 is hot-work steel, and its cost is lower.
The material of the first core rod 12 is hot die steel, and it is specially Switzerland DIEVAR 8418 high performance hot-work die steels.Because the temperature of hot pier section moulding reaches more than 1000 ℃, therefore quite high to the requirement of mold materials, this hot die steel can meet this requirement.
The outer surface of open C jacket ring 10 that is coated on the outer surface of the second core rod 22 is coated with Pre-stress cover 24.This structure can be alleviated the fatigue of mould because brought by large impact power greatly, and exhaust effect is very good, more be conducive to the shaping of 31 liang of salient points 33 of head of product screw rod 3, be difficult for collapsing scarce, ftracture or pull, and conventional mould adopt whole common hot-work steel or whole wolfram steel structure do not have exhaust effect or exhaust effect very poor, that the large impact power rear mold that is subject to mould easily collapses is scarce, ftracture or pull, therefore for mould of the prior art, the present invention can improve the service life (more than one times) of mould greatly.
The second core rod 22 comprises the secondary core rod 222 that the main core rod 221 that contacts with the head 31 of bolt 3 contacts with bar portion 32 with bolt 3, and main core rod 221 and secondary core rod 222 are welded to connect.
The material of main core rod 221 is hot die steel, and it is specially Switzerland DIEVAR 8418 high performance hot-work die steels.Because the temperature of hot pier section moulding reaches more than 1000 ℃, therefore quite high to the requirement of mold materials, that Switzerland DIEVAR 8418 high performance hot-work die steels have is high temperature resistant, shock-resistant, high strength, high tenacity, superior fatigue resistance, therefore can meet this requirement.The material of secondary core rod 222 is wolfram steel.The follow-up rolling screw thread processed that needs of bar portion 32 due to bolt 3, can not there is distortion or pull, therefore it can not participate in distortion, therefore adopt wolfram steel material with the bar portion 32 Contact Pair core rods 222 of bolt 3, the high-wearing feature of wolfram steel, having guaranteed that mould endoporus is more difficult is pulled by product, thereby can guarantee that mould is difficult for by garland, extends the service life of mould.
The cross sectional shape of the first die cavity 13 is the rectangle of chamfering, and the cross sectional shape of the second die cavity 23 is " recessed " font.Wherein the angle between two of the centres vertical curve in " recessed " font and the horizontal line that is all connected with these two vertical curves is greater than 90 degree.
During use, elder generation goes bad 10 at the open C shape cover of the coated one deck spring steel material of outer surface of the first core rod 12 with the first die cavity 13, is pressed in the first formwork 11 after assembling again, and is assembled into punch 1; Then at the outer surface of the second core rod 22 with the second die cavity 23, be coated the open C shape cover bad 10 of one deck spring steel material, outer surface at open C shape cover bad 10 is coated one deck Pre-stress cover 24 again, after assembling, be pressed into together again in the second formwork 23, form die 2.Punch 1 and die 2 are assembled and obtain Split type die of the present invention, the accommodation space of the first die cavity 13 and the second die cavity 23 bolts 3 in besieged city, in present embodiment, being shaped as of bolt 3 is T-shaped.
The announcement of book and instruction according to the above description, those skilled in the art in the invention can also change and revise above-mentioned embodiment.Therefore, the present invention is not limited to the specific embodiment disclosed and described above, to modifications and changes more of the present invention, also should fall in the protection domain of claim of the present invention.In addition,, although used some specific terms in this description, these terms just for convenience of description, do not form any restriction to the present invention.
Claims (9)
1. the hot upset forging mould structure of a stainless steel bolt, it is characterized in that: comprise die and punch, described punch comprises the first formwork, the first core rod and the first die cavity, and described the first core rod is placed in described the first formwork, and described the first die cavity is arranged on described the first core rod; Described die comprises the second formwork, the second core rod and the second die cavity, and described the second core rod is placed in described the second formwork, and described the second die cavity is arranged on described the second core rod, and described the first die cavity and described the second die cavity form the accommodation space of bolt jointly.
2. the hot upset forging mould structure of stainless steel bolt according to claim 1, is characterized in that: the outer surface of described the first core rod and described the second core rod is coated with open C jacket ring, and the material of open C jacket ring is spring steel.
3. the hot upset forging mould structure of stainless steel bolt according to claim 1, is characterized in that: all process through TD on the surface of described the first die cavity and described the second die cavity.
4. the hot upset forging mould structure of stainless steel bolt according to claim 1, is characterized in that: the material of described the first formwork and described the second formwork is hot-work steel.
5. the hot upset forging mould structure of stainless steel bolt according to claim 1, is characterized in that: the material of described the first core rod is hot die steel.
6. the hot upset forging mould structure of stainless steel bolt according to claim 2, is characterized in that: the outer surface of described open C jacket ring that is coated on the outer surface of described the second core rod is coated with Pre-stress cover.
7. the hot upset forging mould structure of stainless steel bolt according to claim 1, is characterized in that: described the second core rod comprises the secondary core rod that the main core rod that contacts with the head of bolt contacts with bar portion with bolt.
8. the hot upset forging mould structure of stainless steel bolt according to claim 7, is characterized in that: the material of described main core rod is hot die steel, and the material of described secondary core rod is wolfram steel.
9. the hot upset forging mould structure of stainless steel bolt according to claim 1, is characterized in that: the rectangle that the cross sectional shape of described the first die cavity is chamfering, the cross sectional shape of described the second die cavity is " recessed " font.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410460977.1A CN104190840B (en) | 2014-09-11 | 2014-09-11 | A kind of hot upset forging mould structure of stainless steel bolt |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410460977.1A CN104190840B (en) | 2014-09-11 | 2014-09-11 | A kind of hot upset forging mould structure of stainless steel bolt |
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| Publication Number | Publication Date |
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| CN104190840A true CN104190840A (en) | 2014-12-10 |
| CN104190840B CN104190840B (en) | 2016-07-20 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201410460977.1A Expired - Fee Related CN104190840B (en) | 2014-09-11 | 2014-09-11 | A kind of hot upset forging mould structure of stainless steel bolt |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105033146A (en) * | 2015-08-13 | 2015-11-11 | 东莞市贝德帕模具科技有限公司 | C-shaped lantern ring split mold |
| CN106607539A (en) * | 2015-10-27 | 2017-05-03 | 陕西宏远航空锻造有限责任公司 | Horizontal-forging forming method for martensitic stainless steel |
| CN106623748A (en) * | 2017-02-24 | 2017-05-10 | 上海索力迪紧固件系统有限公司 | Combined once-punching device for machining screws |
| CN107297449A (en) * | 2017-06-20 | 2017-10-27 | 承德石油高等专科学校 | A kind of metallurgical composite bolt two pass time performing hot-heading forming technique of stainless steel/carbon |
| CN108941415A (en) * | 2018-09-12 | 2018-12-07 | 盐城瑞能精密机械厂 | A kind of the combined type punch die and its manufacturing method of bolt head |
| CN109848353A (en) * | 2019-04-02 | 2019-06-07 | 宏茂五金(昆山)有限公司 | Long size bolt head height one-time-shaped mould |
| CN110976744A (en) * | 2019-12-18 | 2020-04-10 | 高东春 | Novel screw heading device and cold heading processing method thereof |
| USD891242S1 (en) | 2017-10-27 | 2020-07-28 | Assa Abloy New Zealand Limited | Window stay |
| US11091940B2 (en) | 2016-12-23 | 2021-08-17 | Assa Abloy New Zealand Limited | Window stays |
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| JPH0952141A (en) * | 1995-08-17 | 1997-02-25 | Toyota Motor Corp | Bolt forming method |
| CN2564282Y (en) * | 2002-09-02 | 2003-08-06 | 戚玉坤 | Bolt shaping mould |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105033146A (en) * | 2015-08-13 | 2015-11-11 | 东莞市贝德帕模具科技有限公司 | C-shaped lantern ring split mold |
| CN106607539A (en) * | 2015-10-27 | 2017-05-03 | 陕西宏远航空锻造有限责任公司 | Horizontal-forging forming method for martensitic stainless steel |
| US11091940B2 (en) | 2016-12-23 | 2021-08-17 | Assa Abloy New Zealand Limited | Window stays |
| CN106623748A (en) * | 2017-02-24 | 2017-05-10 | 上海索力迪紧固件系统有限公司 | Combined once-punching device for machining screws |
| CN107297449A (en) * | 2017-06-20 | 2017-10-27 | 承德石油高等专科学校 | A kind of metallurgical composite bolt two pass time performing hot-heading forming technique of stainless steel/carbon |
| USD891242S1 (en) | 2017-10-27 | 2020-07-28 | Assa Abloy New Zealand Limited | Window stay |
| CN108941415A (en) * | 2018-09-12 | 2018-12-07 | 盐城瑞能精密机械厂 | A kind of the combined type punch die and its manufacturing method of bolt head |
| CN109848353A (en) * | 2019-04-02 | 2019-06-07 | 宏茂五金(昆山)有限公司 | Long size bolt head height one-time-shaped mould |
| CN110976744A (en) * | 2019-12-18 | 2020-04-10 | 高东春 | Novel screw heading device and cold heading processing method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104190840B (en) | 2016-07-20 |
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